Yieldable pressure applying clamp



Feb. 13, 1940. J. A. WATT 2,190,463

YIELDABLE PRESSURE APPLYING CLAMP Filed July '7, 1938 [III] JAMES A. WATT Patented Feb. 13, 1940 I f I PATENT wa YIE DABL'E PRESSHUREI'ZAPPLYING CLAMP James A. Watt, -Chicago, 111. Application .luly 7, 1938', Serial No. 217,872 'iClaims. (01.24455).

This invention relates to a clamp, and more particularly to a yieldable pressure applying clamp especially adapted for use in clamping fragile material, such, for example, as curtains,

hosiery, film, and many other such articles.

An object of this invention'i toprovide an improved clamp in which provision is made for limiting the amount of clamping pressurethat can be' applied to an article so as to prevent marring of the article by'reason'of-gexcessive pressure being applied thereto.

Another object of this invention is to provide a clamp which may be readily attached :to {or suspended from any'suitable support and which can be tightened into tight cooperation with the material to be clamped without leavi'ng any "objectionable indentation or Imarin the material; Still another object of the invention is to provide an improved clamp which is simple.

and which lends itself to economicalmanufac-I ture on 'a large production basis; e

In accordance with the general features ofthis invention, there is provided a clamp for fragile material and the like comprising opposed clamping jaws connected by tightening means disposed between the extremities of the clamp and manually operative to force the clamping ends of the f jaws at one side of the tighteningmeans' into clamping engagement with the material andbea ing provided with resilient cushioning means at the other side of the tightening'fmeans so ten+ sioned as to' be automaticallyrdisplaceable upon excessive tightening of the tightening means to permit the other ends of the jaws on said 'op'posite side to move toward each other and thus relieve the clamped material from of any further or damaging pressure.

Another feature of the invention relates to the forming of the material engaging-surfaces-of the jaws of a rubber material which is'relatively harder than the; cushioning means, so that the cushioning means of the clamp-will be displaceable much more readily than the rubber material actually in contactwith the article clamped;

Still another feature'ofthe. invention relates to ofisetting the clamping extremities of the clamp so as to cause these extremities to be substantially parallel to each other when the clamp is closed whereby theclamp has a surfaceen gagement with the clamped material rather than merely a line contact. I V r I A further feature of the invention relates to theprovision of means for attaching the clamp to a support which means does not interfere-with the operation of the clamp and whlchmayt'ake sired clamping action;

the application a number of different forms such as an eyelet, a mounting screw, or a suction cup. I

Other objects and featureslof this invention will more fully appear from the following detailed description taken in connection with the accompanying drawing which illustrates several embodiments thereof, and in which:

Figure 1 is a side view of one form of my clamp showing it'applied to material to be clamped;

Figure 2 is a front view of the clamp showing in section the cushioned end thereof and illustrating the clamp in'its open position; s

Figure 3-is a View similar to Figure 2 but showing the clamp closed and in clamping-engagement with material; Figure 4 is a view similar toFigure S'illustrating how the'cushioning rubber is displaced upon the tightening of ,the clamp to' a point beyond that necessary to eifect, clamping engagement with the material held thereby;

Figure 5 is a side view similar to Figure 1 of a modified form of clamp material clamped therebetween and also illus;

trating the cushioning rubber as beingdisplaced by reason of the tightening of the clamp to a point beyond that'necessary to effect the dee Figure '7 isa side view Figure 7, partly in section, and illustrating the action of the clamp.-

As shown on the drawing:

The reference characters lll and ll designate two substantiallyparallelclamping strips which,

or strips, are offset laterally so that these two ends may be propertly characterized as diverging ,endsfThe reason for this is so that'when the clamping ends are brought into clampingjposition as shown in Figure 3',their.'contact surfaces of i still another form of clamp-showing it applied to material; and V Figure 8- is an endlview of the clamp shown in will bein substantial parallelism. If it were 'not.

for this feature, the ends'of the clamping device would only have substantially a line contact. The

use of this feature, however-{enables the clamping extremities o'f'th'e two'jaws l0 and ll to have a very substantial surface engagement *with the material 9 clamped therebetweenp v the best results are obtained by making it of soft rubber, such, for example, as crepe or gum rubber. This feature is advantageous in that the spacer It will be displaced before there is any substantial displacement of the rubber face ings M and I5 when the clamp is tightened into cooperation with the material 9.' a 3 The rubber i6 is illustrated as being tubular and it is mounted on a ferrule or sleeve H which may be made of any suitable material, such, for example, as metal.

The ends of this sleeve or elongated eyelet are clinched over the outer sides ofv the strips in and H as indicated at l8 and 19 so as to limit outward separation of the two strips It! and H and so as to hold the device in assembled condition. 7

Qne advantage of using a tubular connecting me'mber'for connecting'the two strips'li and H and for holding the cushioning" device I5 inplace is that this tubular member l1 may also he used to mount the clamping device on'a suitable support, such, for example, as a hook or the like. I

Located in an intermediate position.- relative to the length of the, clamp. is a tightening device or screw 2!] which is threaded at one end to receive a tightening cap 2| screwed thereon and is threaded and formed into a screw 122 at its other end, which may, if it is so'desired,

be used instead of the eyelet I I to attach the clamping device to a wall. Also threadedupon the end 22 of the tightening device 29 a' nut 23 against which pressure is applied when the cap or nut 2'! is turned for the purpose of moving the clamping jaw or strip H toward the strip ill and into cla. pingi'position. as shown in Figure 3. v I

The operation of this clamp is. briefly, as follows: Normally, when the. clamp is in open position, the two clamping strips or jaws Iii H are substantially parallel to each other, as shown in Figure 2. Upon thetightening of the cap or nut 22 to dispose the" clamp in clamp-- ing enga ement with material 9, th'e'ends i2 and It of the clampingstrips on one-sideof the tightening device are brcught together. as shown in Fi ure 3, with the rubberfacings- M-and E5 in substantial surface engagement with the material 9. k

The material of the cushioning device is tensioned that upon the application of a pre,

determined or excessive amount of tightenin pressure to the two strips in and H, the rubber IE will yield so as to prevent the clampingjaws from marring or forming an indentation in the material and thus damaging the This ac tion is illustrated in Figure 4. In other words, during the tightening-of the clamp and. upon a point being reached where the resistance to further drawing in of the ends i2 and it! is" greater than that aiforded by the cushioning device Hi, this device will yield and will allow ioni'ng. medium; or spacer. [:Of course, if it is- 2,190,463 Also, I have found it desirable, when this clamp the oppositeor'jupper ends of the clamping device to fulcrum about the central tensioning device. In reality, what happens is that the upper end of the strip H pivots or is moved" along the sleeve it towards the upper end of strip. .This results in the displacementof the rubber comprising the spacer I6.

Thus it will be perceived that I have pro-' Vided a clamping device with an intermediate tightening means so related to the opposite extremities of the clamping device that initially the clamping endsof the device will be drawn inwardly toward the material upon the tightening of thedevice into clamping engagement and thereafterafterapredetermined amount of pressure has been. applied the opposite ends of the device will be'caused to be moved toward each other so as to". prevent an excessive amount of pressure from being applied to the material being clamped. -To open the device all that is.

'necessary is to turn the cap or nut 21 on the I Of course, as soon as the pressure of" this tightening device is retensioning element 26.

lieved; the natural resiliency of the rubber spacer It will function to-spread the legs or strips iii and" l I apart and outjof engagement withthe 1 material 9 clamp.-

' In Figures 5 and 6,-I have illustrated a modifi'ed form of clamp similar to the'one shown in the first four figures but differing principally embraced by the free ends of the therefrom in that arubber suction cup 22 is substituted for the, screw and nut 22 and 23 of the first form of the invention. The numorals Hi' to 2! inclusive designate parts of the v 4 clamp. which correspond substantially with.

fparts ill to: 2-l inclusive of the first described form of theinvention. It will be perceivedthat the tightening elementtfi' has a. head .23 :em-

bedded in theymolded suction cup 1-22. I

In the use of. this clamping device, I the operation issubstantially the same asthat of the first described form. Obviously, once the suction cup 2271s pressed down into clamping. en'-. gage'm'ent with asmooth surface ofla suitable support, the jnut or'fc'ap 2!" may be tightened or loosened withoutfinterfering. with the support afiorded by the suctioncup. It should also be noted that in. pressing the suction cup into holdingv cooperation with the/suriace, the

pressure is transmitted from the cap directly, to the cup and not through the material held by the clamp."

In Figures 7 andiiyI have illustrated sun-a 5. further modification of the invention, in which I have substituted,substantially circular plates for the elongated clamping strips of the first two forms of-tlie invention. -These plates are 1 Ha.. These two plates are substantially circu' v designated by the'reference' characters ma "and lar, with the exception-that the clamping plate Mia has a lateralextens'ion' ,l lc'which is aper tured at Hid solthat this extension may be used to support the clamp on a suitable hook or other similar medium. f 1 v At this time, iti'shouldbe noted that in all forms of the invention,- the clamping elements orj awsI-namely, the strips ill-and H, H) and II, and Illa and. Ma,- may'be madeof any suitable rigid material, such, for example, as

metaha phenolic. condensation product, wood,

or any substance of lessresiliency than the cush I so desired, such substance maybe suitably reinforced by insertsbacking or the like.

Each of the two plates "la and Ha has a rubber facing which is in the form of a rubber annulus and which is designated by the reference numerals Ma and [5a. This rubber facing may be secured in any suitable manner to the plate and is preferably made of a soft rubber, such, for example, as crepe rubber.

The two clamping plates 10a and Ila are held in cooperation with each other by a tightening element 200. having-both of its ends threaded, and having threaded on one end a tightening nut 2la-and on its other end a stop nut 23a. It will also be perceived that one of the threaded ends of this element 20a is formed into a screw 22a which may, if desired, be used t o-attach the clamping device to a suitable support, such, fokr example, as a Wall, a window frame," or'the Upon tightening of the clamp into engage-v ment with the material 9, it will be noted from Figure 8 that one side of the clamping'device embraces the material, whereas at the other side the rubber facings are in engagement with each other. As a consequence thereof, it follows that the thickness of the material between the two clamping elements or members on one side of the tightening device will result in the cooking of the plate Ila. with respect to the plate Illa. Moreover, after a predetermined amount of pressure has been applied to the material 9 sufficient to overcome the resistance afforded by the mass of rubber facings, these rubber facings will yield so as to prevent an excessive amount of pressure being applied to the material and thus damaging the material clamped.

From the foregoing, it is apparent that I have provided a simple. clamp which is especiallyadapted for use in connection with-fragile material, such, for example, as curtains, stockings, film and numerous other articles of like character. One application of the clamp which I have found to be particularly useful is where the clamp is used as a means for tying a curtain to a window frame so as to prevent the curtain from flying into the room and against a screen due to currents of air entering the open window.

Another excellent use to which my clamp maybe put is for the purpose of holding up fragile clothing and particularly women's attire, such as undergarments, stockings and the like, after such garments have been washed. The yieldable feature of the intermediate cushioning device, of course, functions at all times to prevent an extensive amount of clamping'pressure from, be-

ing applied to the material engaged so that no indentations or other mars are left in such material by the clamping device. 1 I I I am aware that many changes may be made and numerous details of construction may be varied. through a wide range without departing from the principles of this. invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

1. A clamp comprising opposed clamping jaws, tig htening means disposed between the extremities of the clamp and manually operative to force clamping ends of said jaws at one side of said tightening means into clamping engagement with the material to be clamped, resilient cushioning means at the other side of said tightening means opposite fromsaid clamping side and so, ten

sioned as to be automatically 'displaceable upon further tightening of said tightening meansto permit the other ends of said jaws at said other and'opposite side to movetowards each other and thus relieve saidclamped material from excessive and damaging clamping pressure, said cushioning means comprising resilient spacing means interposed and held between said other ends of said jaws.

2. A clamp comprising opposed clamping jaws, tightening means disposed between the extremities of the clamp and manually operative to force clamping ends of said jaws at one side of said tightening means into clamping engagement with the material to be clamped, resilient cushioning means at the other side of said tightening means opposite from said clamping side and so tensioned as to be automatically displaceable uponfurther tightening of said tightening means to permit the other ends of said jaws at said' other and opposite side to move towards each other and thus relieve said'clamped material from excessive and damaging clamping pressure, said cushioning. means comprising a relatively soft rubber spacer interposed between said other ends of said jaws.

3. A clamp for fragile material and the like comprising opposed clamping jaws, tightening means disposed between the extremities of the clamp and manually operative to force clamping ends of said jaws at one side of said tightening means into clamping engagement with the material to be clamped, resilient cushioning means at the other side' of said tightening means opposite from said clamping side and so tensione'd as to be automatically displaceable upon further tightening of said tightening means to permit the other ends of said jaws at said other and opposite side to move towards each other'and thus relieve said clamped material fromv excessive and damaging clamping pressure, said cushioning means comprising a relatively soft rubber spacer interposed between said other ends of said jaws, said clamping ends of said jaws having their opposed material engaging surfaces formed of rubber having harder characteristics relatively to said rubber spacer.

4. A clamp for fragile material and the like comprising opposed clamping members, means for tightening the members into contact with the material to be clamped, cushioning means associated with said members and said tightening means so as to be stressed-by the tightening of said members into clamping position and effective thereafter upon further tightening of the members to relievesaid'material from any excessive and damaging pressure, said clamping members comprising a pair of opposed disks with said tightening means disposed centrally and and damaging pressure, said clamping members comprising a pair of opposed disks with said tightening means disposed centrally and transversely thereof, one of said circular disks being provided with'an extension formed to serve as a support for attaching the clamp to a wall or the like.

6. A clamp for fragile material and the like comprising opposed clamping jaws, tightening means disposed between the extremities of the clamp and manually operative to force clamping ends of said jaws at one'side of said tightening means into clamping engagement with the material to be clamped, resilient cushioning means at the other side of said tightening means opposite from said clamping side and so tensioned as to be automatically displaceable upon further tightening of said tightening means to permit the other ends of said jaws at said other and opposite side to move towards each other and thus relieve said clamped material from excessive and damaging clam-ping pressure, said cushioning means being connected to said other ends of said jaws by means upon which said other ends may slide inwardly toward each other, said connecting means being tubular so as to constitute an elongated eyelet by means of which the clamp may be extended from a suitable support.

.7. A clamp for fragile material andwthe like comprising opposed clamping jaws, tightening means disposed between the extremities of the clamp and manually operative 'to force clamping ends of said jaws atone side of said tightening means into clamping engagement with the ma- I terial to be clamped, resilient cushioning means at the other side of said tightening means opposite from said clamping side'and so tensioned as to be automatically displaceable upon further tightening of said tightening means to permit the other ends of said jaws at Said other and opposite'side to move towards each other and thus relieve said clamped material from excessive and damaging clamping pressure, said clamping jaws comprising two strips having outwardly offset and diverging end portions at the clamping ends of said jaws which portions are arranged to be brought into substantial parallelism when the clamp is closed into a clamping position so as to have a substantial engagement with the clamped material.

' JAMES A. WATT. 

